Multi-polar electrical medical lead connector system

ABSTRACT

A lead connector is terminated proximally by a connector pin and includes a circumferential array of connector pads, each connector pad coupled to an electrode via an elongated insulated conductor. A lumen of an adaptor is adapted to engage the lead connector and includes an electrical contact zone formed therein and positioned for coupling with a one of the array of connector pads, when the connector is engaged within the lumen, in order to facilitate electrical connection of a selected electrode corresponding to the one of the array of connector pads.

CROSS-REFERENCE TO RELATED APPLICATION

Cross-reference is hereby made to the following commonly assignedrelated U.S. Applications: application Ser. No. ______ to Douglas Hineet al., filed concurrently herewith, entitled MULTI-POLAR ELECTRICALMEDICAL LEAD CONNECTOR SYSTEM (Attorney Docket No. P-11138.00).

FIELD OF THE INVENTION

Embodiments of the present invention relate to implantable medicaldevice connectors and more particularly to a connection system adaptedto allow selection of one or more electrodes from a plurality ofelectrodes included on a medical electrical lead for permanentconnection with the medical device.

BACKGROUND OF THE INVENTION

Implantable medical electrical stimulation and/or sensing leads are wellknown in the fields of cardiac stimulation and monitoring, includingcardiac pacing and cardioversion/defibrillation, and in other fields ofelectrical stimulation or monitoring of electrical signals or otherphysiologic parameters. In the field of cardiac stimulation andmonitoring, endocardial leads are placed through a transvenous route tolocate one or more stimulation and/or sense electrodes, along or at thedistal end of the lead body, in a desired location within a chamber ofthe heart or within a blood vessel of the heart. Epicardial leads arerouted from a subcutaneous site to dispose one or more stimulationand/or sense electrodes, along or at the distal end of the lead body, atan epicardial site on the heart. A pacemaker implantable pulse generator(IPG) or implantable cardioverter/defibrillator (ICD) or monitor,referred to herein generically as an implantable medical device (IMD) iscoupled to the heart through one or more of such endocardial orepicardial leads forming medical system. Means for implanting suchcardiac leads are known to those skilled in the art of pacing anddefibrillation therapy.

Proximal ends of such cardiac leads typically are formed with a leadconnector assembly that is inserted into a connector bore of a connectorblock of the IPG or monitor. The lead body extending distally from theconnector assembly typically includes one or more insulated conductorssurrounded by an outer insulative sheath. Each conductor couples a leadconnector contact of the lead connector assembly with a distalstimulation and/or sense electrode.

More recently, medical electrical leads have been constructed with anarray of pacing and/or sensing electrodes from which one or moreelectrodes may be selected to optimize electrical stimulation therapyand/or monitoring. One example of such a lead is a coronary vein leadimplanted to stimulate a left atrium or left ventricle; other examplesinclude a right atrial or ventricular lead implanted to stimulate anendocardial portion of the right atrium or ventricle or leads implantedto stimulate directly a portion of the cardiac conduction system. Aconnection system for these types of leads needs to be adapted for theselection of one or more electrodes included in the array.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will be more readily understoodfrom the following detailed description when considered in conjunctionwith the drawings, in which like reference numerals indicate identicalstructures throughout the several views, and wherein:

FIG. 1 is a schematic depicting an IMD in part in relation to an adaptorand a connector of a cardiac lead according to one embodiment of thepresent invention;

FIG. 2 is a schematic depicting the IMD of FIG. 1 in part relation tothe connector of FIG. 1 inserted into the adaptor of FIG. 1;

FIG. 3 is an enlarged plan view with a partial cut-away section of theconnector shown in FIG. 1 according to one embodiment of the presentinvention.

FIG. 4 is a radial section view through section line 5-5 of FIG. 3.

FIG. 5 is an enlarged plan view of the adaptor shown in FIGS. 1 and 2according to one embodiment of the present invention;

FIG. 6 is a radial section view through section line 9-9 of FIG. 5;

FIG. 7 is plan view of an adaptor fitted over a lead connector accordingto embodiments of the present invention;

FIG. 8 is a radial section through section line 11-11 of FIG. 7 showingan interface between the lead connector and adaptor according to oneembodiment of the present invention; and

FIG. 9 is a radial section through section line 11-11 of FIG. 7 showingan interface between the lead connector and adaptor according to analternate embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

In the following detailed description, references are made toillustrative embodiments of the invention. The embodiments are describedin the context of a pacing system incorporated in an implantablepacemaker or ICD comprising an ICD or pacemaker IPG (herein collectivelyreferred to as an IMD) and at least one cardiac lead. It will beunderstood that more than one cardiac lead can be coupled to the IMDconnector and extend to the heart in a manner well known in the art. Itwill be understood that the present invention can be incorporated intoother medical electrical leads coupled to other IMD's through adaptorsincorporating the principles of the present invention for deliveringelectrical stimulation elsewhere in the body. It is therefore understoodthat other embodiments can be utilized without departing from the scopeof the invention.

Moreover, adaptors according to the present invention, when assembledwith a lead connector may conform to an industry standard for IMD leadconnectors; however, it is not necessary to the practice of theinvention that the assembly conform to an existing industry standard.Moreover, the degree to which an adaptor of the present invention“up-sizes” the lead connector can range from a negligible up-sizing to asignificant up-sizing without departing from the practice of theinvention.

FIG. 1 is a schematic depicting an IMD 100 in part in relation to anadaptor 20 and a connector 40 of a cardiac lead according to oneembodiment of the present invention and FIG. 2 is a schematic depictingIMD 100 in part relation to connector 40 inserted into the adaptor 20forming an assembly 10. FIG. 1 illustrates connector 40 terminating aproximal end of a cardiac lead 30 and including a set of sealing rings28 and a plurality of lead connector elements including a proximalconnector pin 32 an array of lead connector pads 34, 36, 38circumferentially electrically separated and spaced apart by segments ofan insulator 44; connector pads 34, 36, 38 are arcuate or substantiallyplanar or flattened according to alternate embodiments. According to oneembodiment, connector pin 32 is coupled via an elongated lead conductorto a distal tip pace/sense electrode 52 and each of the plurality oflead connector pads 34, 36, 38 are coupled via elongated lead conductorsextending through lead body 50 to respective distally located pace/senseelectrodes 54, 56, 58 spaced apart along lead body 50 in a distalsegment thereof; one of pace/sense electrodes 54, 56, 58 implanted inproximity to particular pace/sense sites is selected for delivery ofpacing pulses and/or sensing of the electrical signals of a heart inconjunction with electrode 52. For example, FIGS. 1 and 2 illustratecardiac lead 30 implanted in a coronary sinus (CS) of a heart 120 andadaptor 20 is used to select one of the plurality of pace/senseelectrodes 54, 56, 58, which are positioned within a vein 122 branchingfrom the CS. According to alternate embodiments connector pin 32 iscoupled to one of electrodes 54, 56, 58 and each of the plurality ofconnector pads 34, 36, 38 are coupled to distal tip electrode 52 andeach remaining electrode of electrodes 54, 56, 58, from which one isselected by adaptor 20.

As further illustrated in FIG. 1, adaptor 20 includes an elongatedelectrically insulating, tubular adaptor body 22 extending distally froma set of proximal sealing rings 24 and supporting a connector ring 26.According to embodiments of the present invention, a lumen 80 of adaptor20 is sized to receive connector 40 wherein connector ring 26 isinternally configured to make electrical and mechanical contact with oneof the array of connector pads 34, 36, 38; a selection of one of thearray of connector pads 34, 36, 38 being made by rotating adaptor abouta longitudinal axis 2, which will be described in detail below. Outerdimensions of assembly 10 of adaptor 20 positioned over connector 40, asillustrated in FIG. 2, are sized to sealingly mate with a connector bore106 of IMD 100.

FIGS. 1 and 2 illustrate IMD 100 including a connector header 104attached to a wall of a hermetically sealed enclosure 102 that enclosesa battery and electronic circuitry and electrical and other components.Connector header 104 contains at least one connector bore 106 forreceiving assembly 10 of adaptor 20 and connector 40. Connector header104 supports two connector blocks 110 and 108 of any of the known typesthat are electrically connected to the electronic circuitry throughfeedthrough pins of feedthroughs (not shown) that are mounted to extendthrough the wall of the hermetically sealed enclosure 102. Innerdiameters of connector blocks 110 and 108 are dimensioned and positionedin connector bore 106 to receive and make electrical and mechanicalconnection with connector pin 32 and connector ring 26, respectively, ofassembly 10. The electrical and mechanical connection is effectedtypically through the tightening of setscrews (not shown) as disclosedin U.S. Pat. Nos. 4,142,532 and 4,182,345, for example, or the action ofinwardly extending force beams (not shown) as disclosed in U.S. Pat.Nos. 5,070,605 and 5,766,042, for example; both of which are well knownto those skilled in the art. According to embodiments of the presentinvention, assembly 10 is inserted into the connector bore 106, so thatconnector pin 32 and connector ring 26 are seated within the axiallyaligned bores of connector blocks 110 and 108, respectively. Thesetscrews and/or inwardly extending force beams apply force againstconnector pin 32 and compress the adaptor connector ring 26 against oneof the array of connector pads 34, 36, and 38. It will be understoodthat the compression force advantageously traps lead connector 40 withinthe confines of adaptor lumen 80, and that assembly 10 is sealed fromthe environment by compression of sealing rings 24 and 28 within the IMDconnector bore 106.

FIG. 3 is an enlarged plan view with a partial cut-away section ofconnector 40 according to one embodiment of the present invention andFIG. 4 is a radial section view through section line 5-5 of FIG. 3.FIGS. 3 and 4 illustrates array of connector pads 34, 36, 38 includingsurface depressions 64, 66, 68, respectively, and mounted uponinsulating sleeve 44 which extends from sealing rings 28 to connectorpin 32; outward protrusions of insulating sleeve 44 electricallyseparate the adjacent elongated edges of connector pads 34, 36, 38.Means for joining insulating sleeve 44, connector pin 32, connector pads34, 34, 38, and sealing rings 28 to form connector 40 include insertmolding, mechanical interlocks, adhesive bonds, any combination thereof,and/or other methods well known in the art of lead construction. Therelative widths of connector pads 34, 36, 38 and the protrusions ofinsulating sleeve 44 extending between connector pads 34, 36, 38 can beselected in any desired ratio. According to embodiments of the presentinvention, depressions 64, circumferentially spaced at approximately120° from one another, as illustrated in FIG. 4, are elongated axially,as shown, elongated radially or formed in circular dimples; in any suchconfiguration, the slot sides can be ramped.

FIGS. 3 and 4 further illustrate an embodiment of lead 30 wherein theconductors are insulated wires 72, 74, 76, and 78 wound to form of amulti-filar coil 70 including a lumen 60; junctions between wires 72,74, 76, and 78 and respective distal electrodes 52, 54, 56 and 58 (FIGS.1 and 2) are formed by crimps, welds, stakes, or other joining meanswell known to those skilled in the art of lead construction. A proximalend of conductor 72 shown in part by phantom lines extends to leadconnector pin 32, also shown by phantom lines within insulating sleeve44, where it is joined thereto by welding, crimping, staking or othermeans well known in the art. Proximal ends of conductors 74, 76, and 78each extend into respective bores of or against inner surfaces ofrespective connector pads 34, 36, 38 where junctions are formed bywelding, crimping, staking or any other means well known in the art. Inalternate embodiments any combination of wound wire conductors and cableconductors may be incorporated into lead 30, means by which are wellknown to those skilled in the art of lead construction.

FIG. 5 is an enlarged plan view of adaptor 20 according to oneembodiment of the present invention and FIG. 6 is a radial section viewthrough section line 9-9 of FIG. 5. FIGS. 5 and 6 illustrate connectorring 26 of adaptor 20 including a key 82 extending inward throughinsulating adaptor body 22 to function as an electrical contact forcoupling with a selected connector pad from the array of connector pads34, 34, 38 (FIGS. 3 and 4) when connector 40 is inserted within lumen80. Lead connector 40 is manually inserted into adaptor lumen 80 until astop 46 (FIG. 3) abuts a distal end 27 of adaptor and connector pin 32protrudes from a proximal end 29 of adaptor 20 as illustrated in FIG. 7.FIG. 7 is plan view of adaptor 20 fitted over lead connector 40according to embodiments of the present invention and FIG. 8 is a radialsection through section line 11-11 of FIG. 7 showing an interfacebetween key 82 and connector pad 34 according to one embodiment of thepresent invention. According to embodiments of the present invention, inorder to select a connector pad from the array of pads 34, 36, 38,adaptor 20 is rotated about longitudinal axis 2 (FIG. 5) such that key82 is aligned with the selected connector pad upon insertion ofconnector 40 within lumen 80, for example connector pad 34 illustratedin FIG. 9.

According to one embodiment, inwardly extending key 82 is resilient andformed like a force beam, which “gives” in the outward direction whenforce is applied by insertion of connector 40. The inwardly extendingkey 82 can be elongated axially, as shown, ball-shaped like a detentball, or elongated circumferentially, a form dictated only by that ofmating surfaces of connector pads formed on a lead connector, forexample pads 34, 36, 38, in order to facilitate stable electricalcontact between key 83 and connector pads. Furthermore, a mechanicalinterlock between key 83 and the selected pad of pads 34, 36, 38 may beformed, for example with surface depressions 64, 66, 68, which maycreate either a permanent or reversible junction between adaptor 20 andconnector 40 when connector 40 is fully engaged within lumen 80 ofadaptor 20.

Although the above-described embodiments depict the key 82 extendinginwardly from the adaptor connector ring for engagement within of thedepressions 64, 66, and 68, it will be understood that the relativeconfiguration can be reversed as illustrated in FIG. 9. FIG. 9 is aradial section through section line 11-11 of FIG. 7 showing an interfacebetween connector pad 34 and key 82 wherein lead connector pads 34, 36,and 38 are formed having outwardly extending resilient protrusions 64,66, 68 to engage a depression within key 82. According to additionalalternate embodiments, key 82 is disposed in a keyway cut through theadaptor connector ring 26 so that lead connector may be inserted intolumen 80, adaptor may be rotated to position the key way over a selectedconnector pad and then key 82 can then be driven inward to engage theselected connector pad.

It should be understood that, while specific embodiments have beenpresented in the foregoing detailed description of the invention, a vastnumber of variations exist. It should also be appreciated that theexemplary embodiments are only examples, and are not intended to limitthe scope, applicability, or configuration of the invention in any way.For example, four connector pads can be disposed circumferentiallyaround the lead body circumferentially spaced at about 90° from oneanother; six arcuate connector pads can be disposed circumferentiallyaround the lead body circumferentially spaced at about 60° from oneanother, etc.

Moreover, it will be understood that the IMD connector bore can beconfigured to accept a tripolar lead as disclosed in theabove-referenced '042 patent. In that instance, electrical medical lead30 may have first and second connector pad arrays positioned along andeach extending circumferentially around connector 40. A bipolar adaptorwould include first and second spaced apart adaptor connector ringsadapted to make contact with selected ones of the connector pads of therespective first and second connector pad arrays. Still further, it willbe understood that further adaptors may be devised that select more thanone of the distal electrodes coupled to the lead connector pads.

It will be understood that certain of the above-described structures,functions and operations of the above-described embodiments are notnecessary to practice the present invention and are included in thedescription simply for completeness of an exemplary embodiment orembodiments.

In addition, it will be understood that specifically describedstructures, functions and operations set forth in the above-referencedpatents can be practiced in conjunction with the present invention, butthey are not essential to its practice.

It is therefore to be understood, that within the scope of the appendedclaims, the invention may be practiced otherwise than as specificallydescribed without actually departing from the spirit and scope of thepresent invention.

1. A medical system comprising: an IMD including a connector bore; afirst elongated insulated conductor and a plurality of elongatedinsulated conductors; a lead connector including a circumferential arrayof connector pads and terminated proximally by a connector pin, theconnector pin adapted for electrical engagement within the connectorbore; a first lead electrode coupled to the connector pin via the firstinsulated conductor; an array of electrodes, each electrode of the arrayof electrodes coupled to a corresponding connector pad of the array ofconnector pads via a one of the plurality of elongated insulatedconductors; and an adaptor, comprising: a proximal end and a distal end;an internal surface forming a lumen extending from the proximal end tothe distal end, the lumen adapted to engage the lead connector andincluding an electrical contact zone formed therein and positioned forcoupling with a one of the array of connector pads when the connector isengaged within the lumen, and an external surface adapted for engagementwithin the connector bore of the IMD and including a conductive surfaceelectrically coupled to the electrical contact zone and adapted forelectrical connection within the connector bore; wherein, the one of thearray of connector pads corresponds to a selected electrode of the arrayof lead electrodes; and when the lead connector is engaged within thelumen of the adaptor, the connector pin protrudes from the proximal endof the adaptor.
 2. The medical system of claim 1, wherein the externalsurface the adaptor conforms to an industry standard.
 3. The medicalsystem of claim 1, wherein, when the lead connector is engaged withinthe lumen of the adaptor, the external surface of the adaptor and theprotruding connector pin of the connector conform to an industrystandard.
 4. The medical system of claim 1, wherein the external surfaceof the adaptor further includes a set of sealing rings positionedproximal to the conductive surface.
 5. The medical system of claim 1,wherein the lead connector further includes a set of sealing ringspositioned distal to the array of connector pads.
 6. The medical systemof claim 1, wherein the lead connector further includes a mechanicalstop interfacing with the distal end of the adaptor when the leadconnector is fully inserted within the lumen of the adaptor.
 7. Themedical system of claim 1, wherein the electrical contact zone is aninward protruding key.
 8. The medical system of claim 7, wherein theinward protruding key is a resilient force beam.
 9. The medical systemof claim 7, wherein each connector pad of the array of connector padsincludes a surface depression adapted to mate with the inward protrudingkey.
 10. The medical system of claim 1, wherein each connector pad ofthe array of connector pads includes a resilient protrusion adapted tomate with the electrical contact zone.
 11. The medical system of claim10, wherein the electrical contact zone includes an inward protrudingkey having a surface depression adapted to mate with the resilientprotrusion of each connector pad of the array of connector pads.
 12. Amethod for coupling a selected electrode from an array of electrodes toan IMD, comprising aligning a contact zone formed within a lumen of anadaptor with a connector pad selected from a circumferential array ofconnector pads, the selected connector pad corresponding to the selectedelectrode; and inserting the array of connector pads into the lumen ofthe adaptor to electrically couple the selected pad with the contactzone.
 13. The method of claim 12, further comprising inserting theconnector pad array, inserted within the lumen of the adaptor, into aconnector bore of an IMD.